<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="generator" content="rustdoc">
    <meta name="description" content="Source to the Rust file `/home/fmp/.cargo/registry/src/github.com-1ecc6299db9ec823/libc-0.2.34/src/macros.rs`.">
    <meta name="keywords" content="rust, rustlang, rust-lang">

    <title>macros.rs.html -- source</title>

    <link rel="stylesheet" type="text/css" href="../../normalize.css">
    <link rel="stylesheet" type="text/css" href="../../rustdoc.css">
    <link rel="stylesheet" type="text/css" href="../../main.css">
    

    <link rel="shortcut icon" href="https://doc.rust-lang.org/favicon.ico">
    
</head>
<body class="rustdoc source">
    <!--[if lte IE 8]>
    <div class="warning">
        This old browser is unsupported and will most likely display funky
        things.
    </div>
    <![endif]-->

    

    <nav class="sidebar">
        <a href='../../libc/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a>
        
    </nav>

    <nav class="sub">
        <form class="search-form js-only">
            <div class="search-container">
                <input class="search-input" name="search"
                       autocomplete="off"
                       placeholder="Click or press ‘S’ to search, ‘?’ for more options…"
                       type="search">
            </div>
        </form>
    </nav>

    <section id='main' class="content"><pre class="line-numbers"><span id="1"> 1</span>
<span id="2"> 2</span>
<span id="3"> 3</span>
<span id="4"> 4</span>
<span id="5"> 5</span>
<span id="6"> 6</span>
<span id="7"> 7</span>
<span id="8"> 8</span>
<span id="9"> 9</span>
<span id="10">10</span>
<span id="11">11</span>
<span id="12">12</span>
<span id="13">13</span>
<span id="14">14</span>
<span id="15">15</span>
<span id="16">16</span>
<span id="17">17</span>
<span id="18">18</span>
<span id="19">19</span>
<span id="20">20</span>
<span id="21">21</span>
<span id="22">22</span>
<span id="23">23</span>
<span id="24">24</span>
<span id="25">25</span>
<span id="26">26</span>
<span id="27">27</span>
<span id="28">28</span>
<span id="29">29</span>
<span id="30">30</span>
<span id="31">31</span>
<span id="32">32</span>
<span id="33">33</span>
<span id="34">34</span>
<span id="35">35</span>
<span id="36">36</span>
<span id="37">37</span>
<span id="38">38</span>
<span id="39">39</span>
<span id="40">40</span>
<span id="41">41</span>
<span id="42">42</span>
<span id="43">43</span>
<span id="44">44</span>
<span id="45">45</span>
<span id="46">46</span>
<span id="47">47</span>
<span id="48">48</span>
<span id="49">49</span>
<span id="50">50</span>
<span id="51">51</span>
<span id="52">52</span>
<span id="53">53</span>
<span id="54">54</span>
<span id="55">55</span>
<span id="56">56</span>
<span id="57">57</span>
<span id="58">58</span>
<span id="59">59</span>
<span id="60">60</span>
<span id="61">61</span>
<span id="62">62</span>
<span id="63">63</span>
<span id="64">64</span>
<span id="65">65</span>
<span id="66">66</span>
<span id="67">67</span>
<span id="68">68</span>
<span id="69">69</span>
<span id="70">70</span>
<span id="71">71</span>
</pre><pre class="rust ">
<span class="doccomment">/// A macro for defining #[cfg] if-else statements.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This is similar to the `if/elif` C preprocessor macro by allowing definition</span>
<span class="doccomment">/// of a cascade of `#[cfg]` cases, emitting the implementation which matches</span>
<span class="doccomment">/// first.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// This allows you to conveniently provide a long list #[cfg]&#39;d blocks of code</span>
<span class="doccomment">/// without having to rewrite each clause multiple times.</span>
<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">cfg_if</span> {
    ($(
        <span class="kw">if</span> <span class="attribute">#[<span class="ident">cfg</span>($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">meta</span>:<span class="ident">meta</span>),<span class="kw-2">*</span>)]</span> { $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>:<span class="ident">item</span>)<span class="op">*</span> }
    ) <span class="kw">else</span> <span class="op">*</span> <span class="kw">else</span> {
        $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it2</span>:<span class="ident">item</span>)<span class="op">*</span>
    }) <span class="op">=&gt;</span> {
        <span class="macro">__cfg_if_items</span><span class="macro">!</span> {
            () ;
            $( ( ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">meta</span>),<span class="kw-2">*</span>) ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>)<span class="kw-2">*</span>) ), )<span class="op">*</span>
            ( () ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it2</span>)<span class="kw-2">*</span>) ),
        }
    }
}

<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">__cfg_if_items</span> {
    (($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">not</span>:<span class="ident">meta</span>,)<span class="kw-2">*</span>) ; ) <span class="op">=&gt;</span> {};
    (($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">not</span>:<span class="ident">meta</span>,)<span class="kw-2">*</span>) ; ( ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">m</span>:<span class="ident">meta</span>),<span class="kw-2">*</span>) ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>:<span class="ident">item</span>)<span class="kw-2">*</span>) ), $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">rest</span>:<span class="ident">tt</span>)<span class="kw-2">*</span>) <span class="op">=&gt;</span> {
        <span class="macro">__cfg_if_apply</span><span class="macro">!</span> { <span class="ident">cfg</span>(<span class="ident">all</span>(<span class="ident">not</span>(<span class="ident">any</span>($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">not</span>),<span class="kw-2">*</span>)), $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">m</span>,)<span class="kw-2">*</span>)), $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>)<span class="op">*</span> }
        <span class="macro">__cfg_if_items</span><span class="macro">!</span> { ($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">not</span>,)<span class="op">*</span> $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">m</span>,)<span class="kw-2">*</span>) ; $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">rest</span>)<span class="op">*</span> }
    }
}

<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">__cfg_if_apply</span> {
    (<span class="macro-nonterminal">$</span><span class="macro-nonterminal">m</span>:<span class="ident">meta</span>, $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>:<span class="ident">item</span>)<span class="kw-2">*</span>) <span class="op">=&gt;</span> {
        $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">m</span>]</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">it</span>)<span class="op">*</span>
    }
}

<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">s</span> {
    ($($(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">attr</span>:<span class="ident">meta</span>]</span>)<span class="op">*</span> <span class="kw">pub</span> <span class="kw">struct</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>:<span class="ident">ident</span> { $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">field</span>:<span class="ident">tt</span>)<span class="op">*</span> })<span class="kw-2">*</span>) <span class="op">=&gt;</span> ($(
        <span class="macro">__item</span><span class="macro">!</span> {
            <span class="attribute">#[<span class="ident">repr</span>(<span class="ident">C</span>)]</span>
            $(<span class="attribute">#[<span class="macro-nonterminal">$</span><span class="macro-nonterminal">attr</span>]</span>)<span class="op">*</span>
            <span class="kw">pub</span> <span class="kw">struct</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span> { $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">field</span>)<span class="op">*</span> }
        }
        <span class="kw">impl</span> ::<span class="ident">dox</span>::<span class="ident">Copy</span> <span class="kw">for</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span> {}
        <span class="kw">impl</span> ::<span class="ident">dox</span>::<span class="ident">Clone</span> <span class="kw">for</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span> {
            <span class="kw">fn</span> <span class="ident">clone</span>(<span class="kw-2">&amp;</span><span class="self">self</span>) <span class="op">-&gt;</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span> { <span class="kw-2">*</span><span class="self">self</span> }
        }
    )<span class="kw-2">*</span>)
}

<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">f</span> {
    ($(<span class="kw">pub</span> <span class="kw">fn</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>:<span class="ident">ident</span>($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">arg</span>:<span class="ident">ident</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">argty</span>:<span class="ident">ty</span>),<span class="kw-2">*</span>) <span class="op">-&gt;</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">ret</span>:<span class="ident">ty</span> {
        $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">body</span>:<span class="ident">stmt</span>);<span class="op">*</span>
    })<span class="kw-2">*</span>) <span class="op">=&gt;</span> ($(
        <span class="attribute">#[<span class="ident">inline</span>]</span>
        <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">not</span>(<span class="ident">dox</span>))]</span>
        <span class="kw">pub</span> <span class="kw">unsafe</span> <span class="kw">extern</span> <span class="kw">fn</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">arg</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">argty</span>),<span class="kw-2">*</span>) <span class="op">-&gt;</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">ret</span> {
            $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">body</span>);<span class="op">*</span>
        }

        <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">dox</span>)]</span>
        <span class="attribute">#[<span class="ident">allow</span>(<span class="ident">dead_code</span>)]</span>
        <span class="kw">pub</span> <span class="kw">unsafe</span> <span class="kw">extern</span> <span class="kw">fn</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>($(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">arg</span>: <span class="macro-nonterminal">$</span><span class="macro-nonterminal">argty</span>),<span class="kw-2">*</span>) <span class="op">-&gt;</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">ret</span> {
            <span class="kw">loop</span> {}
        }
    )<span class="kw-2">*</span>)
}

<span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">__item</span> {
    (<span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>:<span class="ident">item</span>) <span class="op">=&gt;</span> (<span class="macro-nonterminal">$</span><span class="macro-nonterminal">i</span>)
}
</pre>
</section>
    <section id='search' class="content hidden"></section>

    <section class="footer"></section>

    <aside id="help" class="hidden">
        <div>
            <h1 class="hidden">Help</h1>

            <div class="shortcuts">
                <h2>Keyboard Shortcuts</h2>

                <dl>
                    <dt>?</dt>
                    <dd>Show this help dialog</dd>
                    <dt>S</dt>
                    <dd>Focus the search field</dd>
                    <dt>&larrb;</dt>
                    <dd>Move up in search results</dd>
                    <dt>&rarrb;</dt>
                    <dd>Move down in search results</dd>
                    <dt>&#9166;</dt>
                    <dd>Go to active search result</dd>
                    <dt>+</dt>
                    <dd>Collapse/expand all sections</dd>
                </dl>
            </div>

            <div class="infos">
                <h2>Search Tricks</h2>

                <p>
                    Prefix searches with a type followed by a colon (e.g.
                    <code>fn:</code>) to restrict the search to a given type.
                </p>

                <p>
                    Accepted types are: <code>fn</code>, <code>mod</code>,
                    <code>struct</code>, <code>enum</code>,
                    <code>trait</code>, <code>type</code>, <code>macro</code>,
                    and <code>const</code>.
                </p>

                <p>
                    Search functions by type signature (e.g.
                    <code>vec -> usize</code> or <code>* -> vec</code>)
                </p>
            </div>
        </div>
    </aside>

    

    <script>
        window.rootPath = "../../";
        window.currentCrate = "libc";
    </script>
    <script src="../../main.js"></script>
    <script defer src="../../search-index.js"></script>
</body>
</html>